This research tracks how global proliferation of civilian-owned firearms and US-style permissive gun laws threaten health, equity, and democratic governance in growing numbers of locales worldwide, and how global migrations of guns effect migrations of people. The presentation builds on a recent award-winning book by the author showing how permissive gun laws and dramatic expansions in gun sales lead to profound, and profoundly unequal negative health effects in the US. More guns and loose laws lead to racial and ethnic inequities in safety and security, and empower conservative governance. The current project uses social science, political science, and historical methods to study ways that the US/NRA model goes global—highlighting data and interviews in the US, Middle East, Mexico, and Brazil. Permissive gun laws and civilian-owned firearms undermine efforts to promote equity and public health in growing numbers of locales globally. Potential security benefits to arming civilians are often counterbalanced by rising everyday gun-related injuries and deaths. Gun politics can also be tribalizing, divisive, even antidemocratic. As the author writes, these findings expose “what happens to the soul of a nation—and the meanings of safety and community—when we normalize violence as an acceptable trade-off for freedom.” More guns and weaker gun laws also undermine public-health infrastructure and shape nationalism and anti-immigrant politics—findings supported by the author’s research on the Israeli right and recent research on US-Mexico gun migration patterns. This research speaks directly to the conference sub-theme of Conflict and Peacebuilding. Peace becomes ever-more-elusive when governments encourage citizens to take law-and-order and lethal force it no their own hands. The paper concludes by laying out the vital need for global coordination among gun safety organizations.
In this study, deformation behaviors at the grain level of coarse-grained ultralow carbon steel subjected to uniaxial tension and simple shear were simulated by using a crystal plasticity finite-element method. Heterogeneity of strain distributions appeared at the early stage and remained almost unchanged in the following deformation. Localized strain bands occurred at the grain level, but the directions of the bands depended on the deformation mode. These trends agreed well with experimental results reported in a previous paper [Hama et al., ISIJ Int., 61 (2021), 1971]. The mechanisms that the direction of the localized strain bands depended on the deformation mode were studied on the basis of the slip activities. The activities of slip systems roughly followed the Schmid factor, and the slip directions of the most active slip systems were consistent with the directions of localized strain bands, suggesting that the direction of localized strain bands were determined primarily by the Schmid factor.
In this paper, the effect of cyclic softening properties on fatigue crack propagation behavior was investigated. Ferrite and ferrite-pearlite steels with different cyclic softening properties were produced by cold rolling process. The cold-rolled steels showed cyclic softening, and the cyclic softening rate increased as the cold reduction rate increased. As a result of fatigue crack propagation tests using CT specimens, the fatigue crack growth rate decreased with increasing the cold reduction rate. The crack growth rate and the cyclic softening rate showed a good correlation regardless of the microstructure. The cold-rolled steels showed crack closure/opening behavior, and the crack opening load increased with increasing cold reduction rate. In addition, the difference in the fatigue crack propagation rates of cold-rolled steels was explained by the effective stress intensity factor range. From these results, the decrease of the fatigue crack growth by cold rolling was considered to be mainly due to the suppression of crack opening by cyclic softening near the fatigue crack tip.
The transformation behavior of retained austenite in carburized SCM420H steel and its effect on the change in residual stress on a surface are investigated. The retained austenite on the carburized steel is transformed significantly in the first cycle of fatigue loading with a stress ratio of 1, and the transformation is less significant thereafter. Tensile loading significantly affects the transformation of retained austenite as compared with compressive loading. This is because the mechanical driving force that contributes to the martensitic transformation of retained austenite differs under tensile and compressive stresses. To investigate the transformation behavior of retained austenite and residual stress more comprehensively, an in situ X-ray measurement of retained austenite and residual stress is conducted. In the measurement, retained austenite or residual stress on a specimen surface is measured under loading conditions. Results show that the transformation of retained austenite under tensile loading involves a threshold stress value at which the transformation begins. The transformation of retained austenite proceeds when the applied stress exceeds the threshold value; however, no transformation occurs regardless of the number of loading cycles when the applied stress does not exceed the threshold. The compressive residual stress on the specimen surface increases as retained austenite transforms to martensite due to stress loading.
